Application Of Acyl Cyanides In Organic Synthesis

Small organic molecules, as the economically and environment-friendly catalysts, has received considerable attention in the last few years. The acyl cyanides as a type of useful synthones, can introduce many functional groups in organic synthesis, also recived significant attention. This thesis presents our preliminary research on the application of acyl cyanides in organic synthesis, while using L-proline, there related, and specially designed and synthesized compound, as catalysts.A novel chiral aminophenol 2-(2-hydroxy-phenyl)-oxazolidine-5-carboxylic acid was designed and prepared from (S)-isoserine. Instead of the design product, the final product was a new chiral Schiff base. Interestingly, the solvent plays an important role in crystallizing, only benzene can be used for grow crystal. Between the molecules and the phene molecule exist C-H…p interactions, and the C-H…p interaction is the only notable packing force in the third direction. Therefore, this crystal structure provides an evidence that the C-H…p interaction can in some cases be one Of the major factors stabilizing a crystal structure.In addition, the asymmetric catalytic direct Aldol reaction of acyl cyanides with keotones, catalyzed by L-proline and some amino alcohols, were described in this thesis. 2-hydroxy-4-oxo-2-substituted pentanenitriles were obtained in this reaction, but they were labile and eliminated a molecule of HCN to form 1,3-diketones when treated with base. The products exihibted excellent yields with good regioselectivities, furnishing an efficient and convenient method for the synthesis of 1,3-diketones. cyanohydrine esters were obtained though esterification, this reaction use L-proline as the catalyst, acyl cyanides as the cyanide source, provided a new way for synthesis of cyanohydrine esters.β-Cyanides a,β-unsaturated ketones were synthesized in moderate yields by elimination of CH₃COOH from cyanohydrin esters. In addition,β-nitryl ketones was obtained in the reaction of acyl cyanides with nitromethane, there was no nitryl cyanohydrins formed.